public class Demo{
	public static void main(String[] args) {
		Person person = new Son();
		int result = person.operate(1,2);
		System.out.println(result);
	}
}
class Person{
	public int operate(int a,int b)
	{
		return a+b;
	}
}
class Son extends Person{
	public int operate(int a,int b)
	{
		//调用父类方法实现加操作
		int sum = super.operate(a,b);
		return sum*sum;
	}
}